Can we use weather radar to retrieve volcanic ash eruption clouds? A model and experimental analysis

Real-time areal mapping of a volcanic eruption, in terms of its intensity and dynamics, is usually not possible by conventional visual inspection, especially during poor visibility expected in those circumstances (Barberi et al., 1990). In order to monitor ash cloud patterns, aircraft observations have a limited value, due to their nonsystematic nature and inherent hazards for flights within an ash cloud (Rose and Schneider, 1996). In this respect satellite measurements can offer the advantage of a global coverage with a known temporal repeatability. Satellite visible-infrared radiometric observations from geostationary satellites (e.g., Meteosat sensor) are usually exploited for long-range trajectory tracking and for measuring low level eruptions. Their imagery is available every 15-30 minutes and suffers from a relatively poor spatial resolution (i.e., order of some kilometers). Moreover, the field-of-view of geostationary radiometric measurements may be blocked by water and ice clouds at higher levels and their overall utility is reduced at night.